This invention relates to a ripping apparatus which is particularly effective for penetrating and shattering a railroad bed during forward motion of the vehicle on which it is mounted.
In general, complex rail mounted equipment having an extended length is utilized to reprocess the compacted material of the ballast bed. For example, ballast cleaning and replacement equipment with recirculating excavating chains and conveyor belts have been used to remove and carry ballast from underneath the ties or sleepers to screening and reprocessing equipment, and thereafter to carry the clean ballast back to form a new bed. This equipment must be kept within a predetermined transverse profile in order to pass through bridge tunnels and the like, and to maintain a minimum interference with traffic traveling on an adjacent railbed. Such equipment is also costly to operate and is capable of processing only a limited amount of roadbed length per hour. This is due in part to the high wear rates of the cutting teeth and edges of the chains.
Therefore, it may be appreciated that the low ground speed of the ballast bed cleaning and replacement equipment, and the associated time required to service the equipment, adds to the high cost of operating a railroad. To a significant degree, the highly compacted nature of the ballast bed contributes to these maintenance expenses.
Therefore, what is needed is a ripping apparatus that is able to effectively fracture the earth and ballast bed preparatory to the aforementioned ballast cleaning and replacement equipment. Preferably, the ripping apparatus should be mounted on a self-powered vehicle and include a support arrangement therefor that will enable it to be conveniently positioned into a variety of working attitudes to better match the conditions encountered. For example, the support arrangement should allow effective raising and lowering of the ripping element between the traveling and working modes of operation, and should permit the ripping element to be swung in a substantially horizontal plane between a retracted traveling position and a transversely disposed working position.
Another desirable feature that the ripping apparatus should provide is an extended side reach in order to enable the ripper mechanism to fracture compacted material underneath ties, offset switches, frogs and the like. Moreover, its angle of inclination should be adjustable also, so that the ripping element will draw into the ground when desired or will float at the correct working angle when the vehicle is powered forwardly.
Another problem is that of providing a vehicle and associated ripping apparatus that can travel over either irregular terrain or highways to reach the work area, and can easily be driven into alignment with the ballast bed.
Exemplifying the prior art in the area of track ballast undercutting mechanisms are U.S. Pat. No. 3,436,848 issued Apr. 8, 1969 to R. A. Peppin, et al and West German Pat. No. 2,226,612 issued Jan. 4, 1973. However, such constructions are deficient in that high working forces on the ripping elements are resisted by rotary reversible motors having an inherently poor mechanical advantage with respect to the pivot axis thereof. Accordingly, high working pressures on the motors are required to resist the rotational forces with the attendant disadvantages thereof. While another Patent, namely U.S. Pat. No. 3,457,660 issued July 29, 1969 to M. J. Speno, teaches a construction with a ripping element mounted on a holder pivotally secured to a base plate and a fluid actuated cylinder therefor, such construction is undesirable because of the vulnerability of the working components thereof to damage in use. Particularly, the working components thereof are complex, are disposed in a low elevational disposition, and exhibit a relatively poor mechanical advantage is resisting the rotational forces on the holder.